[Are there any differences between myocardial infarction with Q and non-Q in ECG]

Recent literature provides evidence that Non-Q wave myocardial infarction (Non-Q MI) has a different intrahospital course and prognosis than Q-wave myocardial infarction (Q-MI). We evaluated clinical and laboratory characteristics, complications and therapeutic requirements of 557 consecutive patients, 440 with Q-MI and 117 with Non-Q MI. Risk factors for coronary artery disease did not differ among groups. Non-Q MI patients had a significantly higher incidence of previous cardiac events such as myocardial infarction, angina pectoris and heart failure. Peak CPK enzyme values were significantly lower in Non Q MI patients (952 +/- 753 vs 1,743 +/- 1,425 VI/l p less than 0.05). Early complications were different for both groups: The incidence of heart failure, ventricular arrhythmias and conduction defects was lower in Non-Q MI patients while the incidence of unstable angina pectoris and need for aorto coronary by-pass surgery was higher (18 vs 12%, 17 vs 7% respectively, p less than 0.05). Mortality was not different (8.4% in Non-Q MI vs 12.3% in Q MI). Thus, Non Q MI appears to have a more benign clinical course than Q-MI in terms of less complications such as heart failure, ventricular arrhythmias and conduction defects. However, Non-Q MI is a potentially unstable clinical entity with a higher incidence of early post MI angina pectoris requiring a more aggressive medical and surgical therapy.